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                                                                 Exhibit 10.13



                           SIXTH AMENDATORY AGREEMENT



                 SIXTH AMENDATORY AGREEMENT ("Amendment No. 6"), dated as of
June 30, 1994, among EVI-HIGHLAND PUMP COMPANY, a Delaware corporation
("Highland"), GRANT TFW INC., a Delaware corporation ("Grant"), MALLARD BAY
DRILLING, INC., a Louisiana corporation ("Mallard") (Highland, Grant and
Mallard being hereinafter sometimes collectively referred to as the
"Borrowers"), ENERGY VENTURES, INC., a Delaware corporation (the "Guarantor")
and TRANSAMERICA BUSINESS CREDIT CORPORATION, a Delaware corporation (the
"Lender") to the Amended and Restated Loan and Security Agreement referred to
below.

                 WHEREAS, the Borrowers, the Guarantor and the Lender are
parties to an Amended and Restated Loan and Security Agreement dated October
13, 1992 (the "Original Loan Agreement"); and

                 WHEREAS the Borrowers, the Guarantor and the Lender have
amended the Original Loan Agreement pursuant to (i) a Letter Agreement dated
March 12, 1993 (the "Letter Agreement Amendment"), (ii) a First Amendatory
Agreement dated as of May 5, 1993 ("Amendment No. 1"), (iii) a Second
Amendatory Agreement dated as of August 12, 1993 ("Amendment No. 2"), (iv) a
Third Amendatory Agreement dated as of October 12, 1993 ("Amendment No. 3"),
(v) a Fourth Amendatory Agreement dated as of February  21, 1994 ("Amendment
No. 4") and (vi) a Fifth Amendatory Agreement dated as of March 22, 1994
("Amendment No. 5") (the Original Loan Agreement as amended by the Letter
Agreement Amendment and Amendments No. 1, No. 2, No. 3, No. 4 and No. 5 being
hereinafter referred to as the "Loan Agreement"); and

                 WHEREAS, rather than preparing a new loan agreement, the
Borrowers, the Guarantor and the Lender now desire to further amend and modify
the Loan Agreement;

                 NOW, THEREFORE, in consideration of the mutual covenants
herein contained and for good and other valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties hereto agree as follows:

                 1.       Capitalized terms used but not defined in this
Amendment No. 6 shall have the meanings given to those terms in the Loan
Agreement.

                 2.       The definition of "Net Income After Taxes" set forth
in Article 1 of the Loan Agreement is hereby amended to read in its entirety as
follows:

                 "Net Income After Taxes" shall mean as to any Person and for
                 any period, such Person's net income
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                 after taxes as that term is understood in accordance with
                 GAAP, provided that the calculation of Net Income After Taxes
                 for purposes of Sections 17.02 and 17.05 hereof shall exclude
                 an extraordinary charge to income of approximately $3,800,000
                 net of taxes of approximately $1,900,000 resulting from the
                 refinancing of indebtedness with the proceeds of a private
                 placement by the Guarantor of $120,000,000 principal amount of
                 its 10 1/4% Senior Notes due 2004 completed on March 24, 1994.

                 3.       Except as expressly modified and amended hereby, the
Loan Agreement is ratified and confirmed in all respects.

                 4.       THIS AMENDMENT NO. 6 SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW
YORK.

                 5.       This Amendment No. 6 may be executed in any number of
counterparts and by different parties hereto on separate counterparts, each of
which counterparts, when so executed and delivered, shall be deemed to be an
original and all of which counterparts, taken together, shall constitute but
one and the same Amendment No. 6.

                 6.       This Amendment No. 6 constitutes a modification and
amendment of the existing Loan Agreement and is not a new loan agreement.

                 IN WITNESS WHEREOF, each of the parties hereto has caused this
Amendment No. 6 to be executed by their officers thereunto duly authorized as
of the date first above written.


                                       EVI-HIGHLAND PUMP COMPANY

                                       By:  /s/ JAMES G. KILEY
                                           ---------------------------     
                                           Name:  James G. Kiley  
                                           Title: Vice President


                                       GRANT TFW INC.

                                       By:  /s/ JAMES G. KILEY
                                           ---------------------------       
                                           Name:  James G. Kiley
                                           Title: Vice President


                                       MALLARD BAY DRILLING, INC.

                                       By:  /s/ JAMES G. KILEY
                                           ---------------------------       
                                           Name:  James G. Kiley
                                           Title: Vice President





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                                       ENERGY VENTURES, INC.

                                       By:  /s/ JAMES G. KILEY
                                           ---------------------------      
                                           Name:  James G. Kiley
                                           Title: Vice President-Finance
                                                  & Treasurer


                                       TRANSAMERICA BUSINESS CREDIT
                                       CORPORATION

                                       By:  /s/  MICHAEL J. MCBRIDE
                                           ---------------------------     
                                           Name:   Michael J. McBride
                                           Title:  Vice President





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